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A novel 3D metal/semiconductor nanostructured surface‐enhanced Raman scattering (SERS)‐active substrate is constructed through Ag nanoparticles decoration of flower‐like ZnO nanorods (fZnOs) on a buckled substrate. A thermal treatment is applied to induce substrate buckling and is followed by ZnO hydrothermal synthesis and Ag reduction, resulting in the production of a buckled Ag/fZnOs SERS‐active device. In addition to providing a high areal density of hotspots, surface buckling enhanced the hydrophilicity of the Ag/fZnO composite surface, which aided the adsorption of probe molecules. Buckling also facilitated the formation of eddies in the depressions on the surface, promoting the capture and accumulation of chemicals. Compared with flat Ag/fZnOs, the buckle‐enhanced SERS effects can increase their enhancement factor by over 103 times. The buckled Ag/fZnOs SERS‐active device is recyclable, stable, and inexpensive and is found to be highly sensitive for the detection of Rhodamine 6G and commercial pesticides, achieving a low detection limit of 10−9 m and a high enhancement factor of 2.43 × 108. [ABSTRACT FROM AUTHOR]

Grid‐stiffened composite cylinders are widely used in a variety of applications and are subjected to static, dynamic, and impact loads. In terms of buckling strength, these structures outperform simple layered and sandwich composites of the same weight, and the presence of unidirectional fiber ribs contributes to their delamination resistance. The purpose of this research is to look into the buckling behavior of grid‐stiffened composite cylinders under low‐velocity and high‐energy axial impacts. The tests were carried out at room temperature using a 35 kg impactor with an impactor fall height of about 2.75 m. This study builds on previous research and considers the samples' thin skin, indicating that skin buckling is the primary buckling mode in such scenarios. According to static loading research, three types of buckling can occur in grid‐stiffened composite cylinders: local shell buckling, local rib buckling, and general buckling, and each of these can be controlled by adjusting the geometric properties. But, based on the loading speed in the weight‐drop test, controlling the specific type of buckling that occurs during impact loading is difficult. Examining residual structural effects can help determine the type of buckling and damage sustained during impact events. According to the results, the forces that cause buckling in grid‐stiffened composite structures under impact loads are 1.5–2 times greater than static loading conditions. Notably, once the forces are removed, these structures can return to their original positions, however with less stiffness. As a result, they absorb a significant amount of impact energy. Highlights: Composite cylinders with spiral ribs have higher static compression resistance.Dynamic loading increases local buckling forces in grid‐stiffened structures.Despite being damaged, grid‐stiffened cylinders bounce back quickly after impact.Skin buckling is a common mode of failure for grid‐stiffened composite.The global buckling force is greater than the local buckling force. [ABSTRACT FROM AUTHOR]

Статья посвящена типологическому и хронологическому анализу предметов, обнаруженных в 1999 г. в пещере в северной части седловины горы Развалки (район Кавказских Минеральных Вод). Всего обнаружено около 20 предметов, в числе которых: фрагменты железного меча, включая ромбическое перекрестие; фрагменты железного кинжала; серебряная Г-образная скоба от устья ножен меча; железный топор с узким, слегка выгнутым лезвием и невыделенным обухом (втулка выступает ниже края лезвия); несколько пряжек, в т.ч. серебряные с треугольным щитком, с округлым щитком и со щитком в форме трилистника, украшенным накладкой из тонкого золотого листа с кабошонами из граната (альмандина?); серебряное блюдо на поддоне, украшенное чеканным растительным орнаментом; бронзовая полусферическая чаша; медный клёпанный котел; фрагменты железной очажной цепи из восьмёрковидных звеньев с крюками; фрагменты крюка для вытаскивания мяса и черпака. Большинство предметов дают широкие даты комплекса в пределах IV—VI вв. Ряд предметов имеет достаточно узкие датировки: топор (IV — первая половина V в.), детали поясной гарнитуры (пряжки с треугольным и округлым щитками — вторая половина IV — вторая половина V в., пряжка с выступающим язычком, с альмандинами на щитке в форме трилистника — первая половина — середина V в.). Они являются маркёрами принадлежности комплекса к первой половине —середине V в. Престижный характер большинства изделий —полный набор вооружения (меч, кинжал, топор и наконечник копья с уплощенным пером, обилие предметов из драгоценных металлов (скоба от ножен, пряжки, блюдо), в т.ч. декорированных кабошонами, уникальность чаши, а также разнообразие изделий, связанных, скорее всего, с культом домашнего очага (котёл, очажная цепь и др.) позволяют относить данный комплекс к захоронению представителя княжеского рода.

The article continues the series of publications devoted to the problems of changing cultures in the Kama region at the turn of the early Iron Age and the early Middle Ages. Important in dating these processes are the types of imported brooches. The paper considers the finds of brooches of the Almgren-204 group — with a button at the end of the catch. In total, 10 specimens of such fasteners were found in the Kama region, only in two points – opposite the mouth of the Ik River (Nyrgynda) and in the middle reaches of the Ik River (Sasykul’). In Sarmatian monuments, these types are represented almost exclusively at the mouth of the Don River, and are extremely rare in other areas. A slightly higher concentration is observed in the upper Don region. Another significant problem is the circumstances of the arrival of certain categories of finds in the Kama region. Taking into account the peculiarities of the distribution of fibulae of the Almgren-204 group, their arrival from the «Sarmatians» is hardly possible. Recently, a number of works have appeared that make it possible to trace the chain of «Western» contacts in the I-II (possibly at the beginning of the III) centuries between the Kama region, Sura region (Andreevka-Piseraly monuments), the middle Oka region (monuments of the Upa-2 type), and beyond to north, west and south. The concept was called «the war of the 1st century», although the chronology of events itself is much wider. The considered fibulae with a button at the end of the catch may be one of the markers of these processes.

Abstract We describe a case report of pediatric pars planitis complicated with massive exudative retinal detachment (ERD). A 7-year-old presented with visual acuity (VA) in the right eye (RE) of 6/9 and in the left eye (LE) 6/15. Fundoscopy revealed BE inferior retinoschisis, vitritis and snowballs. He was treated with systemic immunosuppressants. RE retinoschisis resolved within 2 months. Three years later presented with LE VA 6/60 and total ERD. Systemic and intravitreal steroids were administered. Due to refractoriness, he underwent 360° scleral buckle and drainage of subretinal fluid. No retinal breaks or traction were detected. Five months postoperatively LE VA was 6/7.5. Long-term stable outcome was maintained. We report a challenging total ERD as a complication of pars planitis. Although extensive and non-responsive to medical therapy, complete resolution and improvement in vision was achieved with surgical intervention and systemic immunosuppression. We speculate that uncontrolled chronic vasculitic process culminated in diffuse ERD.

Torus fracture of the distal radius is one of the most common pediatric fractures. Though inherently stable, the literature lacks data about the complications or refracture rates after these fractures. The aim of this study was to evaluate the epidemiology of torus fractures of the distal radius in Turkey and to compare rigid and non-rigid immobilization modalities. 598 patients were enrolled in this retrospective study. Medical data such as age, gender, mechanism of the injury, duration and type of treatment were collected as well as the complications during this period. "The Faces Pain Scale – Revised" (FPSR) was used for the assessment of pain before and after the treatment. The mean age was 7.1± 3.6 and the median follow-up was 12 (9-15) months. 181 patients were treated with plaster of paris, 149 with soft casts, 80 with hard casts and 188 with splints. The mean duration of the immobilization was 22.6±5.39 days. FPSR scores before and after the treatment were 2.837(95%CI, 2.686-2.989) and 0.255 (95%CI, 0.186-0.324), respectively (p=0.001). There was no statistically significant difference between the immobilization modalities in terms of FPSR decline before and after the treatment (p=0.403). The overall complication rate was 7.4% among all patients (95% CI, 5.3%-9.5%). Complication rates for each stabilization modality were 13.3% for the plaster of paris, 6.7% for the soft cast, 10% for hard cast and 1.1% for the splint group. The complication rate in the patients treated with splints was statistically significantly lower in the splint group (p=0.001; p=0.033; p=0.002, respectively). The pain was the most common complication (47.8% of all complications). There were 2 refractures during the follow-up period. In conclusion, torus fractures are stable and do not require rigid immobilization. The refracture rate is below 1% and any increase in this rate should be further questioned in order to rule out a misdiagnosis of "green-stick" fracture. [Med-Science 2022; 11(4.000): 1690-6]

The buckle before the lens coating is still typically disassembled manually. The difference between the buckle and the background is small, while that between the buckles is large. This mechanical disassembly can also damage the lens. Therefore, it is important to estimate pose with high accuracy. This paper proposes a buckle pose estimation method based on a generative adversarial network. An edge extraction model is designed based on a segmentation network as the generator. Spatial attention is added to the discriminator to help it better distinguish between generated and real graphs. The generator thus generates delicate external contours and center edge lines with help from the discriminator. The external rectangle and the least square methods are used to determine the center position and deflection angle of the buckle, respectively. The center point and angle accuracies of the test datasets are 99.5% and 99.3%, respectively. The pixel error of the center point distance and the absolute error of the angle to the horizontal line are within 7.36 pixels and 1.98°, respectively. This method achieves the highest center point and angle accuracies compared to Hed, RCF, DexiNed, and PidiNet. It can meet practical requirements and boost the production efficiency of lens coatings. [ABSTRACT FROM AUTHOR]

We describe a case report of pediatric pars planitis complicated with massive exudative retinal detachment (ERD). A 7-year-old presented with visual acuity (VA) in the right eye (RE) of 6/9 and in the left eye (LE) 6/15. Fundoscopy revealed BE inferior retinoschisis, vitritis and snowballs. He was treated with systemic immunosuppressants. RE retinoschisis resolved within 2 months. Three years later presented with LE VA 6/60 and total ERD. Systemic and intravitreal steroids were administered. Due to refractoriness, he underwent 360° scleral buckle and drainage of subretinal fluid. No retinal breaks or traction were detected. Five months postoperatively LE VA was 6/7.5. Long-term stable outcome was maintained. We report a challenging total ERD as a complication of pars planitis. Although extensive and non-responsive to medical therapy, complete resolution and improvement in vision was achieved with surgical intervention and systemic immunosuppression. We speculate that uncontrolled chronic vasculitic process culminated in diffuse ERD. [ABSTRACT FROM AUTHOR]

Torus fracture of the distal radius is one of the most common pediatric fractures. Though inherently stable, the literature lacks data about the complications or refracture rates after these fractures. The aim of this study was to evaluate the epidemiology of torus fractures of the distal radius in Turkey and to compare rigid and non-rigid immobilization modalities. 598 patients were enrolled in this retrospective study. Medical data such as age, gender, mechanism of the injury, duration and type of treatment were collected as well as the complications during this period. "The Faces Pain Scale -- Revised" (FPSR) was used for the assessment of pain before and after the treatment. The mean age was 7.1± 3.6 and the median follow-up was 12 (9-15) months. 181 patients were treated with plaster of paris, 149 with soft casts, 80 with hard casts and 188 with splints. The mean duration of the immobilization was 22.6±5.39 days. FPSR scores before and after the treatment were 2.837(95%CI, 2.686-2.989) and 0.255 (95%CI, 0.186-0.324), respectively (p=0.001). There was no statistically significant difference between the immobilization modalities in terms of FPSR decline before and after the treatment (p=0.403). The overall complication rate was 7.4% among all patients (95% CI, 5.3%-9.5%). Complication rates for each stabilization modality were 13.3% for the plaster of paris, 6.7% for the soft cast, 10% for hard cast and 1.1% for the splint group. The complication rate in the patients treated with splints was statistically significantly lower in the splint group (p=0.001; p=0.033; p=0.002, respectively). The pain was the most common complication (47.8% of all complications). There were 2 refractures during the follow-up period. In conclusion, torus fractures are stable and do not require rigid immobilization. The refracture rate is below 1% and any increase in this rate should be further questioned in order to rule out a misdiagnosis of "green-stick" fracture. [ABSTRACT FROM AUTHOR]

• There are a range of paediatric distal forearm fractures that could potentially be managed with minimal interventions, including either a removable splint or bandage. • There is high-quality evidence to support minimal interventions for children or adolescents with buckle (torus) fractures of the distal forearm. • Although there is growing evidence to support minimal interventions for incomplete, complete, and physeal fractures, well-designed, large, multicentre trials are lacking. • This scoping review highlights the need for further research to delineate exactly which paediatric distal forearm fractures can be managed with minimal interventions, which could benefit the patient and health care system. Distal forearm fractures are common in children and adolescents with a spectrum of severity. There are fracture patterns that are suitable for minimal interventions, such as a splint or bandage. The objective of this review was to identify which types of paediatric distal forearm fractures can be safely and effectively managed with a removable splint or bandage. A scoping review was performed. Databases searched were PubMed, Embase, The Cochrane Library and CINAHL; two trial registries were also searched. All primary study designs with children <18 years of age with a distal forearm fracture that was managed in either a splint or bandage were included. Quality of evidence was determined using the GRADE tool. Twenty-two eligible articles were included from 20 unique studies: 12 randomised controlled trials, seven cohort studies and a case report. Twelve studies focused solely on buckle/torus fractures, with remaining studies including other fracture types, such as incomplete ('greenstick'), complete ('transverse'), or physeal (Salter-Harris). Twelve studies reported that participants with either bandage or splint had appropriate reduction in pain and recovery of function at completion of follow-up for all fracture types. All 20 studies reported minimal adverse events related to fracture management. One study reported worsening angulation with bandage immobilisation for complete fractures in two participants, which required manipulation under anaesthesia. There is high quality evidence to support the safety and effectiveness of a splint or bandage for treatment of distal radius buckle and non-displaced incomplete fractures. Several studies supported the use of minimal interventions for various distal radius cortical breach fracture types, with good outcomes, but were limited by heterogeneity (methodology, interventions, outcome measures, reference standard) and potential bias. Included studies confirmed the inherent stability of buckle fractures. The current literature gap to support minimal interventions for a range of other paediatric distal forearm fracture types was highlighted. High-quality evidence with well-designed, large, multicentre randomised control trials in defined age groups is required to identify which paediatric distal forearm fractures can be safely and effectively managed with either a removable splint or bandage. [ABSTRACT FROM AUTHOR]

The local corrosion of steel plate girder bridges at supports is a major issue affecting the safety. To clarify its effect on the buckling characteristics and bearing capacity, the static tests were carried out. The bearing capacities and local deformation were compared. The local buckling characteristics were refined by stress testing. To further investigate the effect mechanism of corrosion, the global finite element models (FEMs) of bridge were established. Separate corrosion of each component was considered. By comparing the strength and ultimate loads, the key member on bearing capacity reduction was specified. The influence of corrosion scope including the parameters of length, height, and depth on the bearing capacity was clarified. The results show the effect mechanisms of different-member corrosion on bearing capacity reduction were completely diverse. The web corrosion was the main cause of the bearing capacity reduction, which was the first to buckle. The relative position between corrosion scope and the support should also be considered during the evaluation of bearing capacity. [ABSTRACT FROM AUTHOR]

Background: Torus fractures, also known as buckle fractures, of the distal radius are a very common reason for presentation to emergency departments. Traditional approaches to their management involved immobilisation in a circumferential cast but the evidence now supports the use of removable splints with or without radiological and clinical follow-up. Unfortunately current practice conflicts with the evidence base and there is no guideline which highlights all the evidence as one clear, concise management protocol. Methods: An online review of Pubmed, EMBASE, Biomed, and the Cochrane library using keyword searches combining "radius", "torus", "buckle" and "fracture" was performed. All prospective, retrospective or randomised trials involving the management of distal radius torus fractures in patients aged 0–18 years were included. Our outcomes focused on 5 aspects of patient care: immobilisation method and duration, clinical follow-up, radiological follow-up and the use of diagnostic ultrasound. Results: The initial search identified 143 papers which following application of the inclusion and exclusion criteria 21 articles were deemed eligible. A Cochrane review and 8 systematic reviews were also identified and manually searched for missed articles and this yielded a further 3 articles. Conclusions: Current research indicates that torus fractures should be managed with a removable splint supplied in A&E and worn for 3 weeks. There is no need for fracture clinic follow-up or repeat radiological imaging once patients are given adequate information at the time of diagnosis. This would represent both an economical and resource saving for patients, parents and the health service. [ABSTRACT FROM AUTHOR]

When a thin film bonded to a compliant substrate is subject to in‐plane compressive loading, wrinkles on the thin film may form as a consequence of deformation instability. The specimen geometry may also favor global buckling. In this study, a recently developed computational approach is employed to directly simulate 3D wrinkling and buckling from pre‐instability to post‐instability in a straightforward manner, covering a wide biaxial loading spectrum. The finite element models contain an embedded imperfection with perturbed material properties at the film‐substrate interface. This approach is capable of activating the first and subsequent bifurcation modes, along with the deformation patterns in between. It is demonstrated that, in addition to the temporal evolution of wrinkle patterns, surface wrinkling and global buckling can form simultaneously as the substrate becomes thinner. Wrinkles and buckle can either co‐develop, or the buckling‐induced curvature may help facilitate wrinkle formation depending on the specimen thickness and loading biaxiality. Different wrinkle patterns, such as parallel waveform and checkerboard, can even coexist on the same buckled structure. The state of biaxiality can influence the deformation instability significantly, and each bifurcation point can be traced back to certain abrupt changes in the overall load–displacement response. [ABSTRACT FROM AUTHOR]

Soft robotic grippers and hands offer adaptability, lightweight construction, and enhanced safety in human-robot interactions. In this study, we introduce vacuum-actuated soft robotic finger joints to overcome their limitations in stiffness, response, and load-carrying capability. Our design-optimized through parametric design and three-dimensional (3D) printing-achieves high stiffness using vacuum pressure and a buckling mechanism for large bending angles (>90°) and rapid response times (0.24 s). We develop a theoretical model and nonlinear finite-element simulations to validate the experimental results and provide valuable insights into the underlying mechanics and visualization of the deformation and stress field. We showcase versatile applications of the buckling joints: a three-finger gripper with a large lifting ratio (∼96), a five-finger robotic hand capable of replicating human gestures and adeptly grasping objects of various characteristics in static and dynamic scenarios, and a planar-crawling robot carrying loads 30 times its weight at 0.89 body length per second (BL/s). In addition, a jellyfish-inspired robot crawls in circular pipes at 0.47 BL/s. By enhancing soft robotic grippers' functionality and performance, our study expands their applications and paves the way for innovation through 3D-printed multifunctional buckling joints.

The paper continues a series of publications discussing the foundations of dating the beginning of the Piany Bor culture in the Kama region in following two aspects: first, the grounds for the statements about the beginning of the culture in the 3rd century BC, and secondly, to what extent the finds in question correspond to the contemporary chronology. One of the categories is represented by bronze arrowheads. According to the results of unraveling the chains of references, almost all of them come down to the work by M.G. Moshkova in 1962 and K.F. Smirnov in 1961. In the 1980s, there were cardinal changes in the general chronology of the Sarmatian cultures - while maintaining the main features of the rite and inventory of the cultures themselves, the dating of the transition of the Early Sarmatian to the Middle Sarmatian culture has changed from the 2nd century BC to the turn of the epochs. The complexes enabling the dating of the attributes have “rejuvenated”. Bronze arrowheads are still most characteristic of the Early Sarmatian culture, but the culture itself, according to new information, existed before the beginning of the 1st century AD. But, surprisingly, this did not affect the chronology of the local cultures. A review of the cases used by M.G. Moshkova, supplemented by new information, demonstrated that bronze arrowheads have been repeatedly found in the Middle and Late Sarmatian complexes. In certain cases, these are “amulets” made of very archaic types of arrows, and in others, these are items actually used in everyday life. Considering that the placement of arrows in burials of these periods is generally uncommon, it cannot be argued that the existence of arrows is strictly limited to the 3rd century BC. And the dating references of 60 years ago are unacceptable.

The buckle before the lens coating is still typically disassembled manually. The difference between the buckle and the background is small, while that between the buckles is large. This mechanical disassembly can also damage the lens. Therefore, it is important to estimate pose with high accuracy. This paper proposes a buckle pose estimation method based on a generative adversarial network. An edge extraction model is designed based on a segmentation network as the generator. Spatial attention is added to the discriminator to help it better distinguish between generated and real graphs. The generator thus generates delicate external contours and center edge lines with help from the discriminator. The external rectangle and the least square methods are used to determine the center position and deflection angle of the buckle, respectively. The center point and angle accuracies of the test datasets are 99.5% and 99.3%, respectively. The pixel error of the center point distance and the absolute error of the angle to the horizontal line are within 7.36 pixels and 1.98°, respectively. This method achieves the highest center point and angle accuracies compared to Hed, RCF, DexiNed, and PidiNet. It can meet practical requirements and boost the production efficiency of lens coatings.

Inspired by animals with a slippery epidermis, durable slippery antibiofouling coatings with liquid-like wetting buckled surfaces are successfully constructed in this study by combining dynamic-interfacial-release-induced buckling with self-assembled silicon-containing diblock copolymer (diBCP). The core diBCP material is polystyrene- block -poly(dimethylsiloxane) (PS- b -PDMS). Because silicon-containing polymers with intrinsic characters of low surface energy, they easily flow over and cover a surface after it has undergone controlled thermal treatment, generating a slippery wetting layer on which can eliminate polar interactions with biomolecules. Additionally, microbuckled patterns result in curved surfaces, which offer fewer points at which organisms can attach to the surface. Different from traditional slippery liquid-infused porous surfaces, the proposed liquid-like PDMS wetting layer, chemically bonded with PS, is stable and slippery but does not flow away. PS- b -PDMS diBCPs with various PDMS volume fractions are studied to compare the influence of PDMS segment length on antibiofouling performance. The surface characteristics of the diBCPs─ease of processing, transparency, and antibiofouling, anti-icing, and self-cleaning abilities─are examined under various conditions. Being able to fabricate ecofriendly silicon-based lubricant layers without needing to use fluorinated compounds and costly material precursors is an advantage in industrial practice.

A metallurgical and technological characterization of a seventh century bronze buckle coming from the Lombard necropolis of Monte San Zeno in Montichiari (Brescia, northern Italy) was performed to understand the manufacturing techniques. At first, a careful inspection was carried out to highlight the existence of any type of details, which would indicate an intentional design activity or typical casting defects. To avoid destructive measures on the ancient artifact, the buckle was successively characterized only via scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy. This investigation was supported by an accurate study on the chemical composition of the matrix. The results suggest that the buckle was produced by sand casting, although the use of this technique in Europe dates back to the fifteenth century. Finally, based on the results obtained, a faithful archaeometallurgical reproduction of the buckle is proposed. [ABSTRACT FROM AUTHOR]

The steel plate reinforcement is a common method to repair the bearing capacity of the corroded end of the steel girder. The current repair design primarily focuses on improving the local performance under the condition of a pair of stiffeners at the end, with less consideration given to the condition of multiple stiffeners at the end and the evaluation of the overall performance. To clarify the recovery effect of the reinforced steel plate parameters on the bearing capacity of the steel girder, a static loading test was carried out, taking into account the number of stiffeners, the corrosion range, and the reinforced steel plate parameters. The finite element model of the whole bridge was established, and the validity of the specimen size and model were verified. The ultimate load strengthening coefficient and safety coefficient after reinforcement were compared. The influence of steel plate reinforcement parameters on the reinforcement effect was clarified. The results demonstrate that the buckling mode of the corroded end of the steel girder is related to the corrosion range, and the bearing capacity of the steel girder after reinforcement can be restored to original health status. Notably, increasing the coverage range of the reinforced steel plate has a more significant impact on enhancing the reinforcement effect compared to increasing the thickness of the reinforced steel plate. According to the number of end stiffeners and reinforcement conditions, the reasonable value range of the reinforced steel plate parameters is given. • The impact mechanism of the corrosion extent at the corroded end of the steel girder with multi-transverse web stiffeners on the failure mode is elucidated. • The influence of steel plate reinforcement parameters on the reinforcement effect of the corroded end of the steel girder with multi-transverse web stiffeners is clarified. • The reasonable range of steel plate reinforcement parameters for the corroded end of the steel girder is proposed. [ABSTRACT FROM AUTHOR]

A compressively stressed poly (dimethylsiloxane) (PDMS) film with a sputtered gold film can buckle owing to the difference between the Young's modulus of the PDMS film and that of the gold film. The instability of stress is observed at the interface between materials with different Young's modulus. The experiment conducted in this study revealed the important factors that affect the evolution of strips at certain angles at which tensile stress is applied to the elastomer with a ripple pattern. Strips cannot withstand shear stress applied in two different directions simultaneously, resulting in the formation of grids at other angles. Therefore, a dislocation-like movement was observed, proving that Y type dislocations-like exist as well as the displacement of the earth's crust. The fractured surfaces on top of the gold film helped form a pyramid-like pattern. The movement of the dislocation-like and herringbone patterns was recorded using an optical microscope. [ABSTRACT FROM AUTHOR]

By studying the features and contexts of the discovery of annular brooches from Vojvodina the author puts forward a proposal of their typology, in an effort to comprehend their layered functionality, both utilitarian and symbolic - particularly apotropaic. Special emphasis is placed on the interpretation of individual inscriptions. By placing the presented brooches in a broader geographic context and comparing them with analogous finds from neighbouring states, the author reaches interesting conclusions about the time and manner of their use, their potential producers, the directions of their expansion, and the distributors and bearers, highlighting the differences between discrete groups of finds.

The article shows that an important detail of Sambia female outfit, the estias, a mixed form of Sambia belt originated from German and provincial-Roman patterns, dates back to the middle or the third quarter of the I century AD. The emergence of a number of tools of intercultural origin (Sambia belts are among them) presupposes the co-existance of different ethnic groups in Sambia in the Julio-Flavian time.

The presence of a small buckle placed inside a metal box containing eye drops among the furniture of the eye specialist kit of La Favorite (Gallo-Roman Museum of Lyon) has led us to consider this insignificant object as a medical instrument in itself. This discovery is not isolated but these elements have often been interpreted as leather cases residues. The assumption that they would be tourniquets has sometimes been suggested, but rarely relayed. The existence of tourniquets is however well attested in the Greco-Roman medicine. The examination of ancient medical treatises shows that it is not necessary to understand the bloodstream to witness empirically the effects of the indirect compression method. The study of textual sources and the archaeological context of the Lyon furniture invite us to reconsider this working hypothesis.

Background & Objectives: Various methods of immobilization have been recommended for the treatment of torus fracture of distal radius in children. The purpose of this study is to determine if soft bandage is as effective and safe as below elbow circumferential casts in the treatment of torus fracture of the distal radius in the children.Materials & Methods: Children from 4 to 14 years of age, who presented to emergency and outpatient department of orthopaedics and trauma at National Academy of Medical Sciences with an isolated torus fracture of distal radius, were randomized and treated with either soft bandage or below-elbow plaster cast by the same investigators. Patients with associated neurovascular injuries, bilateral torus fractures, concomitant physeal injuries and associated musculoskeletal injuries were excluded. The patients were followed up at weekly interval for 4 weeks and analyzed with VAS, ROM and outcome questionnaire and data were analyzed by using SPSS 18.Results: Among the 114 patients analyzed, 57 patients were kept in soft bandage group and 57 in below-elbow cast group. The mean age in soft bandage group was 8.29 year and the mean age in below-elbow cast group was 8.55 years. There was no significant difference between the two groups with regard to patient demographics, initial fracture characteristics and mechanism of injury.Conclusion: Treatment of distal radius torus fracture with soft bandage is a cost-effective and safe in the children below 14 years of age. These minor fractures are stable and not subject to the risks of late displacement which can be very effectively treated symptomatically to provide pain relief by using soft bandage only and educating the parents about the nature of this paediatrics fracture.Journal of College of Medical Sciences-Nepal, Vol.11(4) 2015: 3-8

The paper describes the fabrication method and the use of a small collection of bone buckles discovered along with the luxurious grave goods from the uncommon burials of the Don-Volga Abashevo culture Second Lipetsk barrow (excavation of 2011). All buckles of Lipetsk kurgan made from fragments compact tubular bones of large ungulates. Tubular bone was split on long longitudinal plates, from which cut out rectangular or square plates smaller size. Then, angles or blanks cut or grind off by means an abrasive to achieve a circular or oval shape. On the external and internal surfaces of buckles fixed multidirectional traces of thin and very fine abrasive. After abrasive processing workpieces, large and small holes are drilled. As a rule, the central holes drilled into the buckle first. Buckles after drilling was worked up fine abrasive. Traces of wear visible on all the buckles from burials 2 of Lipetsk kurgan. Using of buckles occurred with varying intensity. The ratio the wear and tear, both surfaces of buckles allows you to reconstruct the position of items in operation and consider them as belt buckles. Graphic reconstruction of fixing bone buckles to the straps is given in the article as well.

More than dozen bone figured buckles of Babyno type were found in the Priazovye and in territory of Ukraine. Semi-oval bead without hole is located under the belly on short trims. Some researchers consider it as a hook, by which fastened belt. A series of pendants that had an annular frame, which is attached by a thin trims to the bead with transverse hole, refers to this time. Apparently figured buckles, on the one hand, have been genetically linked to the cheek-pieces (system connections with belt ribbon), and on the other - with pendants of Liventsovka type, whose elements are bead fixed to the lath, at the end of which there was a ring of pendants. In Lakedemonovo burial in one of the burials, on the bone of the pelvis, bone bead in the form of a keg was found, which, apparently, is a kind of clasp. These findings relate to the propagation time Babyno sites in Priazovye.

The solvent‐provoked formation and evolution of thin film buckling‐delamination on a compliant substrate have been studied. The film surface is observed by an optical microscope showing a remarkable dynamic buckling‐delamination development and a subsequent stable branched‐straight state. It is revealed that the initiation, propagation, and the resulting patterns of film buckles are strongly dependent on the solvent type, film stress, interfacial adhesion, and film thickness. The buckling could be controlled further by a reasonable chemical solvent configuration and used to provide useful information for the pattern creation on polymer systems in diverse fields, such as micro/nanofabrication and optics. [ABSTRACT FROM AUTHOR]

Emerging flexible electronics industries, such as solar cells and RFID tags manufactures, adopt the roll-to-roll (R2R) technology to improve their production efficiency. However, the flexible webs used in these fields wrinkle easily due to their tiny thickness and complex structure. Moreover, the webs are easily buckled if the rollers are misaligned. Therefore, it is desired to introduce an efficient method which can help to determine the critical buckling conditions of the webs when there is misalignment of rolls during their production. The current research presents a model based on the Kirchhoff plates buckling theory to determine the critical buckling misalignment and tension for webs transported through misaligned rollers. Webs are modeled as tensioned Timoshenko beams to obtain their stress distributions. The critical buckling conditions are calculated using the Galerkin method in the current research. Results indicate that the calculated critical conditions are close to the practical ones considering the parabolic variation of shear stress and the linear variation of bending stress. The results also indicate that the critical misalignment increases with the increase of the span ratio and tension, and critical misalignment decreases with the increase of the elastic modulus and web width. Moreover, the critical tension increases as the thickness and elastic modulus increases. The presented model provides a useful method to design and maintain R2R equipment. [ABSTRACT FROM AUTHOR]

The cell membrane is one of the most important structures of living organisms. This is due to the many functions attributed to it such as permeable selectivity, protection, anchoring to the cytoskeleton and so many others. Any change in the shape of the cell membrane may affect directly the properties and abilities. In this article, we study how defects in the liquid crystalline organization of a membrane can change its shape. For performing this, we consider a membrane with orientational order, i.e., a nematic membrane, which can happen in biological membranes, nematic films and other systems and study how a defect in this order can change the shape of the membrane when the bending rigidity is considered. We find that depending on the ratio of rigidity and elastic constant, buckling of this membrane may happens and turn it into pseudo-spheres.

Based on the theory of elastic mechanics, a dynamical model of an encapsulated gas microbubble under ultrasound is presented. The dynamical motion of the microbubble is divided into three states: buckled, elastic, and ruptured. The model describes the compression-only behavior appropriately and derives the transient variation of the resonance frequency of the damped oscillation and the relation between the critical rupture radius and initial outer radius. The normal stress in the tangential direction plays the principal role in the rupture and buckling of the encapsulating shell, resulting in likely rupture for a larger microbubble and resistance to rupture for a thicker-shell microbubble. Comparison of proposed dynamical model with Marmottant's model has been given. The dynamical model can be employed in ultrasound medical diagnostics and therapy of drug incorporation or extravasation through further understanding the influence of the encapsulating shell. [ABSTRACT FROM AUTHOR]

Adhesion of thin metal films on dielectric substrates is one of the most important properties in microelectronic devices due to the fact that interface adhesion determines the device lifetime and reliability. In order to improve the lifetime of these devices, substrate treatments and adhesion layers are often utilized, making a quantitative assessment of adhesion of the utmost importance. A key example of a metal film common in many microelectronic devices is Tungsten-Titanium (WTi), which is used as a diffusion barrier and an adhesion layer. Several testing methods and mechanics-based models have been developed over the last decades to quantitatively evaluate interface adhesion of thin metal films on rigid substrates. For thin films on rigid substrates (i.e. dielectrics or silicon) the most viable methods are mechanical techniques such as nanoindentation and scratch induced delamination because of the simplicity of the test setup and sample preparation. During indentation or scratching, stresses are induced into the film system which can cause interface separation in the form of buckles. By measuring the dimensions of the buckle and employing the appropriate model, the interfacial adhesion energy can be quantitatively determined. These techniques were utilized to induce interface delamination of a WTi film on different borophosphosilicate glass (BPSG) substrates. The comparison of the results from the different techniques will provide more insight into the techniques applicability and help to better characterize the adhesion of similar film systems. [ABSTRACT FROM AUTHOR]

• The strengthening efficiency was improved significantly for the slabs with hybrid anchored (HA) CFRP. • The surface treatment had a marginal influence on the strengthening effect of slabs strengthened with HA CFRP. • The strength of the slabs strengthened with HA CFRP decreased with the length of CFRP sheets. Reinforced concrete (RC) slabs are widely strengthened in flexure by externally bonding (EB) carbon-fiber-reinforced polymer (CFRP) sheets, where debonding failure remains a critical issue. To solve the debonding problems, a self-locking device is initially proposed to enhance the anchorage at the end of FRP sheets for strengthening of RC slabs in this study. The effects on the debonding resistance and the improvement of the strengthening efficiency are experimentally investigated. Six one-way RC slabs strengthened with end-buckled and/or externally bonded CFRP sheets were prepared for the four-point bending tests. All strengthened specimens had higher ultimate loads than the reference specimen. While the slab strengthened by EB CFRP had a limited increase in ultimate load, the improvement was significant for the cases with hybrid anchored (HA) CFRP including both end-anchorage and external bonding, which was 46.2%. In this case, the interfacial stresses could be reduced and the end debonding can be avoided due to the increasingly tight anchoring effect, and the ultimate load can be increased even after partial debonding since the stress can continue to be transferred via mechanical anchorage. When the specimens were strengthened with HA CFRP, the surface treatment had a marginal influence on the strengthening effect. The strength of the slabs strengthened with HA CFRP decreased with the length of CFRP sheets, which is contrary to the trend of cases using EB CFRP. Finally, expressions were proposed to estimate the strain of the CFRP and load-carrying capacity of the strengthened members at the ultimate state, and the test results were within the range of the calculated results. [ABSTRACT FROM AUTHOR]

Subsidence is a geologically hazardous phenomenon that can be aggravated by human such activities as long term water, oil, and gas extraction from underground resources or other mining activities. Abstractions from aquifers cause the aquifer-maintaining forces to lose their state of equilibrium whereby land starts to settle and ultimately subsides. One of the consequences of exploiting groundwater is the rising of well casings. Actually, it is not the well casings that rise but the ground around them that subsides. Subsiding forces can damage well casings and this can foist repair costs, or the wells might even need to be replaced by new ones. In this paper ,finite element methods in two and three dimensional modes as well as ABAQUS software were used to investigate the impacts of subsidence from groundwater exploitation and drawdown on well casings. This investigation was based on data obtained from a real basin. The results obtained through geomechanical simulations using ABAQUS software have shown that the mechanism by which subsidence "bowls" are created cause two forms of rupture in the casings. At the edges of the bowl, surface sediments might slide on soft clay toward the center of the well and cause the casings to bend along their way. Around the center of the bowl something different happens. Considerable compaction of soft clay over time causes the distance between the surface and the bottom of the well to decrease, which results in the buckling of the casings and, in some cases, causes the casings to stick out of the ground.

Microfabricated devices have increasingly incorporated bacterial cells for microscale studies and exploiting cell-based functions in situ. However, the role of surface interactions in controlling the bacterial cell behavior is not well understood. In this study, microfluidic substrates of varied bacterial-binding affinity were used to probe the interaction-driven behavior of filamentous Escherichia coli. In particular, cell alignment under controlled shear flow as well as subsequent orientation and filamentation were compared between cells presenting distinct outer membrane phenotypes. We demonstrated that filaments retained position under flow, which allowed for dynamic single-cell monitoring with in situ elongation of over 100 μm for adherent cells. This maximum was not reached by planktonic cells and was, therefore, adhesion-dependent. The bound filaments initially aligned with flow under a range of flow rates and their continual elongation was traced in terms of length and growth path; analysis demonstrated that fimbriae-mediated adhesion increased growth rate, increased terminal length, as well as dramatically changed the adherent geometry, particularly buckling behavior. The effects to filament length and buckling were further exaggerated by the strongest, specificity-driven adhesion tested. Such surface-guided control of the elongation process may be valuable to yield interesting "living" filamentous structures in microdevices. In addition, this work may offer a biomedically relevant platform for further elucidation of filamentation as an immune-resistant morphology. Overall, this work should inspire broader exploration of microfabricated devices for the study and application of single bacterial cells. [ABSTRACT FROM AUTHOR]

Transparent, stretchable films of carbon nanotubes (CNTs) have attracted significant attention for applications in flexible electronics, while the lack of structural strength in CNT networks leads to deformation and failure under high mechanical load. In this work, enhancement of the strength and load transfer capabilities of CNT networks by chemical vapor deposition of graphene in the nanotube voids is proposed. The graphene hybridization significantly strengthens the CNT networks, especially at nanotube joints, and enhances their resistance to buckling and bundling under large cyclic strain up to 20%. The hybridized films show linear and reproducible responses to tensile strains, which have been applied in strain sensors to detect human motions with fast response, high sensitivity, and durability. [ABSTRACT FROM AUTHOR]

Bending characteristics of individual thin-walled carbon nanotubes (CNTs) are investigated through a novel in-situ nanoindentation in transmission electron microscopy. Unlike thick-walled CNTs, the graphitic layers of thin ones buckle into V-shaped kinks rather than Yoshimura ripples. These kinks are found to be entirely reversible without residual plastic deformation following unloading. [ABSTRACT FROM AUTHOR]

The collision and rebound behavior of ping pong balls impinging onto rigid target are studied. Three dimensionless dominant parameters are identified: (1) the ratio of the wall-thickness to the average radius of the ball; (2) the dimensionless initial velocity; and (3) the yield strain of the material. Depending on the dimensionless initial velocity, various collision and rebound behaviors of the ball are revealed: (1) When the initial velocity is low, the deformation of the ball remains purely elastic, for which the characteristic duration is theoretically obtained; (2) With the increase of initial velocity, the ball's cap begins to buckle and multiple impacts occur, leading to the increase of the restitution duration and the reduction of the coefficient of restitution (COR); (3) With the higher initial velocity, the ball's cap buckles permanently, leading to the disappearance of multiple impacts and a sudden drop of the restitution duration; consequently the COR decreases from 0.5 to 0.3; and (4) When the initial velocity is close to the material's yield velocity, the ball buckles into a non-axisymmetric mode. The simulation results are also compared with experimental ones. Furthermore, the effects of thickness-to-radius ratio, yield strain and coefficient of friction are also discussed. [ABSTRACT FROM AUTHOR]

Pipe inspection and maintenance are necessary to prevent economic and casualty losses due to leakage of fluids from damaged pipes. In-pipe soft robots made of highly deformable materials have been proposed to meet the needs, yet most of those comprise multiple segments and require multiple actuators controlled independently, resulting in less compact structures and more demanding control schemes. In this study, we harness the highly nonlinear buckling of elastic ribbons and bioinspired artificial muscles to significantly enhance the crawling capability of a single-actuator soft robot. Our prototype robot consists of a McKibben pneumatic actuator surrounded by three longitudinally arranged elastic ribbons. These tailored ribbons are three-dimensional (3D) printed and can be buckled into highly deformed 3D shapes upon inflation of the actuator. First, we show that the robot exhibits strong anisotropic friction when fully buckled. Then, we demonstrate that by simple open-loop on/off control, our robot achieves robust crawling in horizontal, vertical, bent pipes and even wet pipes partially or filled with water. It can also adapt to pipes with some variations in diameter. Using only one actuator lowers the complexity of robot structure and pneumatic system, offering high potential for new applications at different scales.

Applying heat treatment to buckled steel construction elements especially at the time of disaster, are accepted as temporary repairs. This study aims to turn temporary retrofits applied to steel structural elements into permanent repairs using an additional operation. To this end, experimental and numerical investigations were conducted to remedy weaknesses observed in elements repaired with heat treatment by gluing fiber-reinforced polymer plates to them. Experimental and parametric studies show that a permanent repair can be achieved by affixing GFRP plates to locally buckled steel structures after heat treatment. In addition, a formula is presented to calculate the critical buckling stress in GFRP-reinforced steel plates based on the slenderness ratio. [ABSTRACT FROM AUTHOR]